2024 Recommendations for Validation of Noninvasive Arterial Pulse Wave Velocity Measurement Devices

Advanced vascular aging and outcomes after acute ischemic stroke: a systematic review and meta-analysis

Pulse wave velocity (PWV) is as a reliable marker of arterial stiffness and vascular aging, surpassing traditional risk factors in predicting detrimental cardiovascular events. The present meta-analysis aims to investigate PWV thresholds and assess its prognostic value in outcomes of acute ischemic stroke (AIS). A search was conducted in PubMed, Cochrane, Web of Science, and Scopus for studies published up to January 2024, focusing on patients admitted with AIS, wherein arterial stiffness was assessed through PWV measurements during hospitalization. Identified studies reported PWV values in individuals with both favorable and unfavorable outcomes at the end of follow-up. Initially, 35 eligible studies provided data for weighted mean baPWV (11,953 AIS patients) and cfPWV (2,197 AIS patients) calculations. The average age was 67 years, with approximately 60% male, 67% hypertensive, 30% diabetic and 30% smoker participants. The weighted mean systolic blood pressure was approximately 150 mmHg. In AIS patients, the mean PWV was 10 m/s for standard cfPWV and 20 m/s for baPWV. Nine cohort studies (6,006 AIS patients) were included in the quantitative analysis of clinical outcomes. Higher PWV levels were associated with poorer functional outcomes (2.3 m/s higher, 95%CI:1.2-3.4, p < 0.001; I2 = 87.4%). AIS patients with arterial stiffness/vascular aging (higher PWV) had approximately 46.2% increased risk of poor functional outcome, 12.7% higher risk of mortality, 13.9% greater risk of major adverse cardiovascular events, and 13.9% greater risk of stroke recurrence over the long term compared to those without arterial stiffness. Advanced vascular aging, as indicated by PWV, significantly predicts adverse outcomes in AIS patients. Integrating the assessment of vascular aging into clinical practice can improve risk perception in these patients.

Cardiovascular Aging and Risk Assessment: How Multimodality Imaging Can Help

Aging affects the cardiovascular system, and this process may be accelerated in individuals with cardiovascular risk factors. The main vascular changes include arterial wall thickening, calcification, and stiffening, together with aortic dilatation and elongation. With aging, we can observe left ventricular hypertrophy with myocardial fibrosis and left atrial dilatation. These changes may lead to heart failure and atrial fibrillation. Using multimodality imaging, including ultrasound, computed tomography (CT), and magnetic resonance imaging, it is possible to detect these changes. Additionally, multimodality imaging, mainly via CT measurements of coronary artery calcium or ultrasound carotid intima-media thickness, enables advanced cardiovascular risk stratification and helps in decision-making about preventive strategies. The focus of this manuscript is to briefly review cardiovascular changes that occur with aging, as well as to describe how multimodality imaging may be used for the assessment of these changes and risk stratification of asymptomatic individuals.

Clinical Validation of Carotid-Femoral Pulse Wave Velocity Measurement Using a Multi-Beam Laser Vibrometer: The CARDIS Study

BACKGROUND

Carotid-femoral pulse wave velocity (cfPWV) is the gold standard for noninvasive arterial stiffness assessment, an independent predictor of cardiovascular disease, and a potential parameter to guide therapy. However, cfPWV is not routinely measured in clinical practice due to the unavailability of a low-cost, operator-friendly, and independent device. The current study validated a novel laser Doppler vibrometry (LDV)-based measurement of cfPWV against the reference technique.

METHODS

In 100 (50 men) hypertensive patients, cfPWV was measured using applanation tonometry (Sphygmocor) and the novel LDV device. This device has 2 handpieces with 6 laser beams each that simultaneously measure vibrations from the skin surface at carotid and femoral sites. Pulse wave velocity is calculated using ECG for the identification of cardiac cycles. An ECG-independent method was also devised. Cardiovascular risk score was calculated for patients between 40 and 75 years old using the WHO risk scoring chart.

RESULTS

LDV-based cfPWV correlated significantly with tonometry (r=0.86, P<0.0001 ECG-dependent [cfPWVLDV_ECG] and r=0.80, P<0.001 ECG-independent [cfPWVLDV_w/oECG] methods). Bland-Altman analysis showed nonsignificant bias (0.65 m/s) and acceptable SD (1.27 m/s) between methods. Intraobserver coefficient of variance for LDV was 4.7% (95% CI, 3.0%-5.5%), and interobserver coefficient of variance was 5.87%. CfPWV correlated significantly with CVD risk (r=0.64, P<0.001; r=0.41, P=0.003; and r=0.37, P=0.006 for tonometry, LDV-with, and LDV-without ECG, respectively).

CONCLUSIONS

The study demonstrates clinical validity of the LDV device. The LDV provides a simple, noninvasive, operator-independent method to measure cfPWV for assessing arterial stiffness, comparable to the standard existing techniques.

REGISTRATION

URL: https://clinicaltrials.gov/study/NCT03446430; Unique identifier: NCT03446430.

Assessment of aortic stiffness during atrial fibrillation: solutions and considerations

Background

Methods to assess aortic stiffness are not validated during ongoing atrial fibrillation (AF) We aimed to determine whether aortic stiffness can be assessed reliably in patients during AF.

Methods and results

Carotid-to-femoral and aortic pulse wave velocity (cf/aoPWV), central blood pressure (BP), and augmentation index (AIx) were assessed by a two-site applanation method and a one-site cuff-based oscillometric method in 40 patients with persistent AF and repeated after cardioversion to SR. Mean age was 63 ± 8 years, 73% male, 50% hypertensive. For the two-site method, cfPWV values were slightly higher in AF than in SR (9.3 ± 1.8 vs. 8.5 ± 1.6 m/s, p < 0.001), whereas the one-site method provided similar values in AF and SR (10.1 ± 1.5 vs. 10.0 ± 1.8 m/s).The variability indices from the device was higher in AF for the two-site method (SD 2.5 ± 1.7 vs. 1.0 ± 0.5 m/s, p < 0.001) but similar in AF and SR with the one-site method (SD 0.7 ± 0.2 vs. 0.6 ± 0.2 m/s). Both methods yielded higher central BP (+4.8/+6.6 and +4.1/+5.7 mm Hg) and lower Aix (-6.8 and -9.1 mm Hg) in AF.

Conclusions

Aortic stiffness can be assessed during AF. Both methods yielded higher central BP and lower AIx in AF, but similar results for PWV in AF and SR, also when adjusted for BP changes. The two-site method showed high variability necessitating repeated measurements. The one-site method showed lower device-calculated variability and needed fewer repeated measurements.

Pulse Wave Velocity: Methodology, Clinical Applications, and Interplay with Heart Rate Variability

Pulse wave velocity (PWV) has been established as a promising biomarker in cardiovascular diagnostics, providing deep insights into vascular health and cardiovascular risk. Defined as the velocity at which the mechanical wave propagates along the arterial wall, PWV represents a useful surrogate marker for arterial vessel stiffness. PWV has garnered clinical attention, particularly in monitoring patients suffering from vascular diseases such as hypertension and diabetes mellitus. Its utility extends to preventive cardiology, aiding in identifying and stratifying cardiovascular risk. Despite the development of various measurement techniques, direct or indirect tonometry, Doppler ultrasound, oscillometric analysis, and magnetic resonance imaging (MRI), methodological variability and lack of standardization lead to inconsistencies in PWV assessment. In addition, PWV can be estimated through surrogate parameters, such as pulse arrival or pulse transit times, although this heterogeneity limits standardization and, therefore, its clinical use. Furthermore, confounding factors, such as variations in sympathetic tone, strongly influence PWV readings, thereby necessitating careful control during assessments. The bidirectional relationship between heart rate variability (HRV) and PWV underscores the interplay between cardiac autonomic function and vascular health, suggesting that alterations in one could directly influence the other. Future research should prioritize the standardization and increase comparability of PWV measurement techniques and explore the complex physiological variables influencing PWV. Integrating multiple physiological parameters such as PWV and HRV into algorithms based on artificial intelligence holds immense promise for advancing personalized vascular health assessments and cardiovascular care.

Serum Endocan Is a Risk Factor for Aortic Stiffness in Patients Undergoing Maintenance Hemodialysis

Background and Objectives: Endocan, secreted from the activated endothelium, is a key player in inflammation, endothelial dysfunction, proliferation of vascular smooth muscle cells, and angiogenesis. We aimed to investigate the link between endocan and aortic stiffness in maintenance hemodialysis (HD) patients. Materials and Methods: After recruiting HD patients from a medical center, their baseline characteristics, blood sample, and anthropometry were assessed and recorded. The serum endocan level was determined using an enzyme immunoassay kit, and carotid-femoral pulse wave velocity (cfPWV) measurement was used to evaluate aortic stiffness. Results: A total of 122 HD patients were enrolled. Aortic stiffness was diagnosed in 53 patients (43.4%), who were found to be older (p = 0.007) and have a higher prevalence of diabetes (p < 0.001) and hypertension (p = 0.030), higher systolic blood pressure (p = 0.011), and higher endocan levels (p < 0.001), when compared with their counterparts. On the multivariate logistic regression model, the development of aortic stiffness in patients on chronic HD was found to be associated with endocan [odds ratio (OR): 1.566, 95% confidence interval (CI): 1.224-2.002, p < 0.001], age (OR: 1.040, 95% CI: 1.001-1.080, p = 0.045), and diabetes (OR: 4.067, 95% CI: 1.532-10.798, p = 0.005), after proper adjustment for confounders (adopting diabetes, hypertension, age, systolic blood pressure, and endocan). The area under the receiver operating characteristic curve was 0.713 (95% CI: 0.620-0.806, p < 0.001) for predicting aortic stiffness by the serum endocan level, at an optimal cutoff value of 2.68 ng/mL (64.15% sensitivity, 69.57% specificity). Upon multivariate linear regression analysis, logarithmically transformed endocan was proven as an independent predictor of cfPWV (β = 0.405, adjusted R2 change = 0.152; p < 0.001). Conclusions: The serum endocan level positively correlated with cfPWV and was an independent predictor of aortic stiffness in chronic HD patients.

The effect of cardiorespiratory fitness and habitual physical activity on cardiovascular responses to 2 h of uninterrupted sitting

Prolonged uninterrupted sitting of >3 h has been shown to acutely cause central and peripheral cardiovascular dysfunction. However, individuals rarely sit uninterrupted for >2 h, and the cardiovascular response to this time is currently unknown. In addition, while increased cardiorespiratory fitness (CRF) and habitual physical activity (HPA) are independently associated with improvements in central and peripheral cardiovascular function, it remains unclear whether they influence the response to uninterrupted sitting. This study sought to 1) determine whether 2 h of uninterrupted sitting acutely impairs carotid-femoral pulse wave velocity (cfPWV), femoral ankle PWV (faPWV), and central and peripheral blood pressure and 2) investigate the associations between CRF and HPA versus PWV changes during uninterrupted sitting. Following 2 h of uninterrupted sitting, faPWV significantly increased [mean difference (MD) = 0.26 m·s-1, standard error (SE) = 0.10, P = 0.013] as did diastolic blood pressure (MD = 2.83 mmHg, SE = 1.08, P = 0.014), however, cfPWV did not significantly change. Although our study shows 2 h of uninterrupted sitting significantly impairs faPWV, neither CRF (r = 0.105, P = 0.595) nor HPA (r = -0.228, P = 0.253) was associated with the increases.NEW & NOTEWORTHY We demonstrate that neither cardiorespiratory fitness nor habitual physical activity influence central and peripheral cardiovascular responses to a 2-h bout of uninterrupted sitting in healthy young adults.

Medical device regulation in vascular ageing assessment: a VascAgeNet survey exploring knowledge and perception

BACKGROUND

Regulation has a key role for medical devices throughout their lifecycle aiming to guarantee effectiveness and safety for users. Requirements of Regulation (EU) 2017/745 (MDR) have an impact on novel and previously approved systems. Identification of key stakeholders' needs can support effective implementation of MDR improving the translation to clinical practice of vascular ageing assessment. The aim of this work is to explore knowledge and perception of medical device regulatory framework in vascular ageing field.

RESEARCH DESIGN AND METHODS

A survey was developed within VascAgeNet and distributed in the community by means of the EUSurvey platform.

RESULTS

Results were derived from 94 participants (27% clinicians, 62% researchers, 11% companies) and evidenced mostly a fair knowledge of MDR (despite self-judged as poor by 51%). Safety (83%), validation (56%), risk management (50%) were considered relevant and associated with the regulatory process. Structured support and regulatory procedures connected with medical devices in daily practice at the institutional level are lacking (only 33% report availability of a regulatory department).

CONCLUSIONS

Regulation was recognized relevant by the VascAgeNet community and specific support and training in medical device regulatory science was considered important. A direct link with the regulatory sector is not yet easily available.

The Role of Carotid-Femoral Pulse Wave Velocity in a Metabolic Syndrome Patient with Sudden Cardiac Arrest: A Case Report

INTRODUCTION

Carotid-femoral pulse wave velocity reflecting aortic stiffness could be used as an independent predictor of future cardiovascular events for an individual with metabolic syndrome. However, the routine use of carotid-femoral pulse wave velocity is suboptimized in clinical practice. We report a case of metabolic syndrome with increased carotid-femoral pulse wave velocity and subsequently developed myocardial infarction and sudden cardiac arrest.

CASE PRESENTATION

A Polish man of an age between 40 and 50 years previously diagnosed with metabolic syndrome with essential hypertension, obesity, dyslipidaemia, and impaired glucose level. He developed myocardial infarction, ventricular fibrillation, and was successfully resuscitated with defibrillation. The patient showed high-normal traditional cardiovascular risk factors but an increased carotid-femoral pulse wave velocity. The increased carotid-femoral pulse wave velocity is associated with an increased arterial stiffness, which altered the myocardial perfusion and induced the anterior-lateral ST elevation myocardial infarction. The patient actively participated and completed the phase II cardiac rehabilitation programme. To the best of our knowledge, there have been few studies on carotid-femoral pulse wave velocity screening for patients with metabolic syndrome. Pulse wave velocity screening by a physician appears to be helpful in identifying the potential high-risk population with borderline traditional cardiovascular risk factors.

CONCLUSION

This trajectory highlights the clinical relevance of using carotid-femoral pulse wave velocity as an adjunct marker to assess the risk of cardiovascular event for patients with metabolic syndrome.